As we refrain from intervention domestically in the interest of encouraging productive trade, we should be guided by a defeasible presumption of non-intervention on the international stage in the interest of preventing this undesirable variety.

I understand your reluctance to rely on it exclusively you're looking for an airtight argument and the morality argument has limits and problems of its own - being defeasible by a contrary moral imperative, for example, but that's the argument that gets the most traction.